Transcript enzymes - Coosa High School

ENZYMES
Enzymes are Catalyst
• Enzymes speed up
chemical reactions.
•Enzymes are catalyst
to over 4000
biochemical reactions!
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Life Sciences-HHMI Outreach. Copyright 2009 President and Fellows of Harvard College
Activation Energy
Enzymes work by
lowering the
activation energy
needed to start a
chemical reaction.
http://en.wikipedia.org/wiki/File:Activation_energy.svg
Life Sciences-HHMI Outreach. Copyright 2009 President and Fellows of Harvard College
Enzymes are Reusable
• Enzymes are reusable
molecules found in
living things
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Life Sciences-HHMI Outreach. Copyright 2009 President and Fellows of Harvard College
Classifying Enzymes
• There are 4 major categories of macromolecules:
carbohydrates, lipids, proteins, & nucleic acids
• Most enzymes belong to the class of proteins.
• However, there are a few catalytic RNA
molecules.
Life Sciences-HHMI Outreach. Copyright 2009 President and Fellows of Harvard College
Naming Enzymes
• Take the name of the substrate the enzyme works
on and add the suffix -ase
• Example: Lactose  Lactase
– Galactose  Galactase
– Fructose  Fructase
– Protein  Protease
– Lipid  Lipase
Life Sciences-HHMI Outreach. Copyright 2009 President and Fellows of Harvard College
Enzyme Form and Function
• Lock & key Model: The shape of an enzyme
allows it to do a specific job much like a lock and
key.
Life Sciences-HHMI Outreach. Copyright 2009 President and Fellows of Harvard College
Induced Fit Model
• Enzymes can form to the shape of its
substrate.
http://en.wikipedia.org/wiki/File:Induced_fit_diagram.svg
Life Sciences-HHMI Outreach. Copyright 2009 President and Fellows of Harvard College
Denaturing Enzymes
• When an enzyme is denatured it is
damaged.
• Denaturing changes the shape.
• Without the correct shape enzymes won’t
function properly.
• HOW are enzymes denatured?
– Temperature
– pH
Life Sciences-HHMI Outreach. Copyright 2009 President and Fellows of Harvard College
What other factors control the
action of enzymes?
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Temperature
Water Content
pH
Chemicals
Alteration of Substrates
Alteration of Products
Enzyme Inhibitors
• Chemicals that prevent the enzyme from working.
• Inhibitors decrease the enzyme reaction rate
• Certain Drugs, Pathogens, Pesticides, and
Metabolic Imbalances are Inhibitors.
• Found in Nuts, Grains, Legumes and Seeds
Life Sciences-HHMI Outreach. Copyright 2009 President and Fellows of Harvard College
Enzyme Activators
• Chemicals that help the enzyme work.
• Activators increase the enzyme reaction rate
• Inorganic Compounds, Vitamins are Activators
– Called Cofactors
Active
Site
Activator
X
Binding
Site
Substrate
Life Sciences-HHMI Outreach. Copyright 2009 President and Fellows of Harvard College
Enzymes are used all over your body!
http://upload.wikimedia.org/wikipedia/commons/thumb/6/6f/Major_digestive_enzymes.png/750px-Major_digestive_enzymes.png
Life Sciences-HHMI Outreach. Copyright 2009 President and Fellows of Harvard College
Enzyme Deficiency
Protease Deficient:
Cannot digest protein
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causes blood to be more acidic
Can't produce glucose
Inadequate hydration in the body
Problems include:
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Arthritis
Bone spurs
Hypoglycemia
Edema (swelling)
Toxic Colon
Ear infections in children
Compromised Immune System
Predisposed to PMS
Enzyme Deficiency
Lipase Deficient:
Lipase digests fats and fat-soluble vitamins
Problems include:
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High Cholesterol
Difficulty losing weight
High triglycerides
Decreased cell permeability(can't get glucose out
of cells
Muscle Spasms
Chronic Fatigue Syndrome
Spastic Colon
Vertigo
Early Menopause
Enzyme Deficiency
Amylase Deficient:
Amylase digests starches and polysaccharides – end
result is glucose
Also digests dead white blood cells (pus)
Can be cause by excessive consumption of
Carbohydrates
Problems Include:
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Skin problems: Abscesses, Psoriasis, Eczema,
allergic reactions to bee stings
Lung problems: asthma and emphysema
Phosphorus deficiency
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Thick blood
Gastritis
Enzyme Deficiency
Sucrase Deficient
Cannot split sucrose into glucose
Glucose is basically brain food
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Problems include: moodiness, depression,
panic attacks, manic and schizophrenic
behavior, severe mood swings and seizures.
Lactase Deficient
Cannot digest lactose
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Causes cramping and diarrhea
FOOD ENZYMES
Properties of Food Enzymes
• Control ripening.
• Cause food spoilage (rotting).
• Responsible for changes in flavor,
color, texture and nutritional
properties.
• Can be inactivated by heat to
extend storage stability of foods.
Properties
• Used for fermentation purposes in
foods.
• Can be extracted and purified
Applications in food industry
• Carbohydrases: production of corn
syrups from starch (glucoamylase);
conversion of cereal starches into
fermentable sugars in malting, brewing,
distillery, baking industry (amylase).
Applications in food industry
• Proteases: meat tenderizers (bromelin,
papain, ficin)
• Lipases: Flavor production in chocolate
and cheese
Food Enzymes: Denaturing
with Heat
• Denaturation occurs at 104°F or
hotter.
• Too much heat slows and stops
enzyme activity.
– Destroys enzymes that alter
food quality.
– Example -- blanching
vegetables to prevent spoilage
during frozen storage.
B-3.03 -- Denaturation of Enzymes
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Food Enzymes: Denaturing
with pH
• Changing the pH can speed up, slow, or
stop enzymatic reactions
– Lemon juice to Apples
– Citric Acid to Shrimp
B-3.03 -- Denaturation of Enzymes
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Food Enzymes: Denaturing
with Salts
• Salt is commonly used in food
production
– Binds to enzymes in food that
cause spoilage
• Used in canning
– Decreases microbial growth
• Water in foods = bacterial
growth
• Salt causes osmotic shock to
bacterial cells = cell death
B-3.03 -- Denaturation of Enzymes
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Food Enzymes: Denaturing
with Enzyme Inhibitors
• Naturally occurring
– Egg whites
– Pesticides that are naturally part of a plant
structure
• Marigolds
• Chrysanthemums
• Synthetic compounds
– Prescription Drugs
B-3.03 -- Denaturation of Enzymes
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Enzymes in Foods
• Enzymes in raw food start the digestion
process in the body and reduce the body's
need to produce digestive enzymes\
– In humans: A diet composed mostly of cooked
foods puts strain on the pancreas due to
constant production of enzymes
• Can cause enlargement of pancreas and shrinkage of
other organs such as the brain.
Enzymes in Foods
• Foods with High Enzyme content
– Extra Virgin Olive Oil, raw honey, grapes, figs
and tropical fruits such as avacado, dates,
bananas, pineapple, kiwe, papaya and mangos
• Raw peanuts and potatoes are Enzyme
inhibitors (prevent enzymes from working)
– Put strain on digestive organs
– Fermentation and Cooking foods avoid this
– Nuts and Seeds: Store in refrigerator and soak
in purified water for 24 hours.